1. Field of the Invention
The present invention is directed to cooling containers for beverages and other foods, and more particularly pertains to double-wall containers which hold a quantity of chillable or freezable fluid that can be cooled or frozen without damage to the container.
2. Description of the Prior Art
The use of double-wall containers for keeping beverages and other foods cold is well known in the prior art. In this respect, reference is made to U.S. Pat. No. 4,520,633, to R. Hoydic on June 4, 1985. The Hoydic apparatus comprises a bowl for keeping food chilled which is separable into two parts to include an upper food-containing receptacle and a lower ice-containing chamber. Inasmuch as the two bowl sections are slidably attached together, slidable relative movement therebetween is afforded during a freezing of the ice in the lower container. In this respect, it is well known that the freezing of virtually any fluid from its liquid state into a frozen solid state results in an expansion of its overall volume If means are not provided for an expansion of the retainer in which the fluid is contained, the container is subject to damage and rupture.
U. S. Pat. No. 4,485,636, which issued to R. Hilado on Dec. 4, 1984, also recognizes the necessity of providing room for expansion of an enclosed refrigerant. More particularly, the Hilado device comprises a container of a double-wall structure, with such wall structure forming a refrigerant cavity for holding a fluid which, when frozen, produces a cooling of a beverage or food in the container. A stress-relieving diaphragm accommodates the expansion of the fluid upon a chilling thereof so as to prevent breakage of the container. While the Hilado container is functional for its intended purpose, reference to the drawings enclosed with this patent will disclose the fact that it is of a substantially complex design. Inasmuch as complexities of design cause a concurrent increase in the expense of manufacture, the Hilado container has apparently not met with commercial success.
As such, there appears to be a continuing need for new and improved double-walled containers which can hold a refrigerant wherein such containers may be inexpensively and easily manufactured, and in this respect, the present invention substantially fulfills this need.